A 79-year-old man with no prior medical history arrived at a hospital in Dammam, Saudi Arabia, after a witnessed seizure, and then his right arm began acting without him. It rose, moved with apparent purpose, and repeatedly struck his own body and face. He could describe exactly what it was doing. He could not stop it.
The neurologists who watched those movements documented the case in BMC Neurology. Their diagnosis was alien hand syndrome, a rare disorder in which a limb produces coordinated, goal-directed movements that the person experiences as foreign. The patient repeatedly described the limb as "moving on its own."
